Logo

75 Horse BF75S1300828 Water not pumping

stu

Member
"I have a 1981(?) 7.5

"I have a 1981(?) 7.5 Honda. I replaced the impeller and everything seemed to go together fine but nothing comes out of the pisser and it heats up when I tested it. I tried blowing back through the tube leading to the tell tale but it seems completely blocked (maybe that's normal?).

I figured it might be the thermostat but I'm not quite sure where to find it. I pulled a cover under the front part of the flywheel but there was no water in it and even with it off I can't get any air through anywhere I might expect the water to go. Does anyone know of or have a diagram that I can download? Or maybe someone could email me one?

Also, is this likely the problem - or is there somewhere else that a blockage can occur?

The motor runs nicely but I don't want to kill it with heat.

By the way, thanks to all who helped me on my Mariner 60 - I took it out for its maiden voyage yesterday and it purred like a kitten."
 
"Stuart,

You definitely hav


"Stuart,

You definitely have a blockage in the cooling system. Frequently the top of the water tube gets clogged after an overheating incident, but it could also be salt or other debris accumulating in the exhaust or at the base of the powerhead.

Tony"
 
"hey stuart, i had the same pr

"hey stuart, i had the same problem, if you have a look at my last post, i explained what i had done to my b75, and now i got heaps of water running through and out....the thermostate is on your left hand side( looking at the engine from the prop end), next to the head, it looks like a triangle with 3 bolts, take that off, then the other bolts from the plate behind, and make sure all the water jackets are open, and no carbon build up on the plate.if you wanna send me an email. i'll post some pictures of what you have to do. regards, muzza"
 
"Thanks Muzza. My 75 has a la

"Thanks Muzza. My 75 has a larger grey plate that houses the thermostat, cooling ports, and some of the exhaust ports. The thermostat was pretty disgusting and two of the cooling ports were totally clogged. It took longer to clean the old gasket material off the plate and surfaces than anything else.

It all seems to work pretty well now. 25 year old motor that purrs like a kitten. Of course I've only used it twice for about 30 minutes at a shot."
 
Back
Top